1. Field of the Invention
The present invention relates to an image processing apparatus and a method for controlling the same.
2. Description of the Related Art
With the widespread availability of image forming apparatuses such as multifunction peripherals having multiple functions in recent years, anybody can now easily copy or transmit documents. This has brought improved convenience to users, but also has increased the risk of information leakage that occurs when copying or transmitting confidential documents.
For the purpose of preventing and monitoring such information leakage, an image forming apparatus has been proposed in which image data and log information of various jobs such as copy jobs or print jobs are produced and then stored in a storage device (Japanese Patent Laid-Open No. 10-503901).
This technology makes it possible to track which user has printed or transmitted a leaked document.
Meanwhile, a network document management system has been proposed in which a server that stores image data and document data in association with document identification information such as keywords is connected via a network to clients who request processes including information retrieval from the server, displaying, and printing. As used herein, image data and document data include those produced by reading printed letters, figures, and images with a scanner and those produced with a word processor or the like.
Also, an image forming system has been proposed in which information stored in the apparatus of Japanese Patent Laid-Open No. 10-503901 is transmitted and registered using this network document management system as an archive server, so that clients can retrieve and browse the information.
However, when storing image data in an archive server on a network, the image forming apparatus needs to be capable of communication with the archive server through the network. For example, if an output is copied or printed according to the instruction of a copy or print job of the image forming apparatus in a state in which communication is not possible due to a network failure or the archive server being down, the image data and log information for tracking are not stored. This creates security problems.
It is also possible to employ a configuration in which image data and log information to be transmitted to the archive server are stored temporarily in a storage unit included in the image forming apparatus, the image data is printed, and the stored image data and log information are transmitted when communication is re-established. This configuration provides an advantage that an operator can immediately receive the product of a job he/she already submitted, that is, a printed paper output if the job is, for example, a copy job or print job. However, there is a risk that the product may be leaked during the time period until the server recovers, creating a security loophole.
Further, even when a network failure has been repaired or the archive server has recovered, and communication has been re-established, archive server breakdown of the image forming apparatus or a malicious attack such as, for example, causing physical damage can lead to the image data and log information remaining untransmitted to the archive server, which in turn leads to a security problem.
When communication between the image forming apparatus and the archive server is not possible, the security problem can be eliminated by controlling the image forming apparatus not to accept a copy or print job, even when the apparatus is operating normally. However, despite the fact that the image forming apparatus is operating normally, the operator needs to submit the copy job, print job, or the like again, which causes inconvenience to the operator.
The image forming apparatus may be used as follows: the image forming apparatus is connected directly to a personal computer (PC), and paper documents are scanned using a software application that runs on the PC through a scanner driver.
In this case, if the image forming apparatus has a storage device that can store a large amount of image data, like the apparatus of Japanese Patent Laid-Open No. 10-503901, no problem arises. However, some low-price scanners and multifunction peripherals do not have a hard disk, or even if they have a hard disk, the capacity thereof is small, so they have a problem that they are not suitable for storing image data.
When the archive server is located on a network and image data is stored in the server, no problem arises if the image forming apparatus is connected directly to the archive server through the network, but when the image forming apparatus is not connected to the network, the following problems occur.
When the image forming apparatus is not connected directly to the network on which the archive server is located, in the case of the above-described example, the image forming apparatus needs to transmit images to the archive server via the PC connected to the image forming apparatus. However, with the use of another apparatus or software, information leakage may be caused by malicious users.
For example, such malicious users can alter images to be transmitted using software in the PC, or can make the image forming apparatus appear to have sent images to the archive server by imitating the response from the archive server, when in fact the image forming apparatus has not sent the images.